martin luther king jr. president and mrs. obama rolled up their sleeves today with 500 volunteers at an elementary school in northeast. vice president joe biden and his wife jill prepared care packages at the national guard armory for u.s. troops and first responders. on the national mall, a day of service summit just wrapped up a f few minutes ago. >> jim, darkness is set unwilling here now on the national mall. but today volunteers in the big white tent behind me were lighting up the place. thousands of people poured through the national day of service tent headquarters already to volunteer like jennifer artist and her two sons of little river, maryland. >> it's important to have my children with me because they get to see the importance of serving others. and we're also celebrating martin luther king's day and this is something that he would want us to do as well. >> how about 100 public and private, local and national groups of all types offered volunteer encouragement. what is best buddies? >> best buddies creates opport